Dynamics Analysis Of Perforating Columns In An Oil Field In South China Sea

The perforating operation of offshore oil and gas fields is a key link in the oil and gas production process,and it is also an effective technical means to increase oil and gas production capacity.Due to the insufficient study on the response law of the dynamic loading of perforation tubular string in the sea,accidents such as damage and destruction of perforated string occur from time to time.For this purpose,this paper aims at perforating columns commonly used in offshore oil and gas fields,and uses ANSYS LS-DYNA software to carry out targeted simulation simulations of perforating bullets and perforating strings,and studies the dynamic response of perforating strings during perforation.Firstly,using ANSYS LS-DYNA software to establish the perforation string model of a single perforation projectile,and simulate the perforation process to obtain the variation law of the jet velocity and energy,and the acceleration and velocity response of the central position of the perforation string.Then the software was used to build simulation models of perforating guns and tubings for multiple perforating bullets.The perforating process of multiple perforating bullets was simulated.Acceleration response characteristics of perforating tubing and perforating guns and perforation string stress were obtained.Change over time.Finally,based on the simulation model of single and multiple perforating bullets,a reasonable simplification method for finite element simulation modeling of perforated tubulars is proposed.This method is used to analyze the typical perforation plan of an oil field in the South China Sea,and the position of percussive column dangerous point and the maximum equivalent stress value are obtained.The fourth strength theory is used to judge the safety of the tubing at this location,which is consistent with the field data.The modal analysis of the oil pipe shows that the oil pipe is susceptible to resonance of the first-order vibration mode,and the natural frequency can be changed by increasing the length of the oil pipe to avoid resonance,thereby improving the safety of the pipe string in the perforating process.